For what it is worth these lamps operate at some 900 - 1000 deg C; so keeping the room at normal 72 - 78 deg F should be fine. I doubt dropping the temperature 5- 10 degrees is going to make much difference in the long run to lamp life. Just make sure the fans are working, which all PJ's check continually and you should be fine.
High altitude settings are there to compensate for the thinner air which does not cool as efficiently; so using faster fan setting help to compensate for that lack.
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